Have had this issue for a while, finally decided it annoyed me enough to see if anyone else experienced the same. Basically, when I am finished working on a parts using the Orchestral Companion series I get audio glitches when I try to render/bounce the audio. This can be notes cutting out abruptly or not being played at all in the resulting file.

I am using a Macbook Pro and have tested in Logic, Live and Reaper with the same result every time in each.

Not that I should be bothering with this, but my workaround is to render each stem dozens of times and comp the takes until I get one solid performance on each track.

Thanks for the reply! Yes I had tried that first, I should have mentioned. Same result whether I allocate a buffer of 32 or 2048 samples and everything in between.

It may also be of relevance that I've an SSD and 16gb RAM and I can generally run other large sample libraries with no issues and at low latency. I don't think my machine is being taxed, though I'm open to suggestions.

When you have a pluginfolder in your Daw on your Mac, remove one by one the third party plugins which are not included with you DAW and move them to another folder so you can put them back in your DAW plugin folder on your system If they do not cause the problem.
Every time you remove a plugin restart your DAW ore rescan your plugins.